Generally, a disk brake mounted on a vehicle, such as an automobile, includes a mount member fixed to a non-rotatable portion of the vehicle, a caliper provided on this mount member displaceably in an axial direction of the disk, a pair of friction pads configured to be pressed against both surfaces of the disk by the caliper, and pad springs installed on the mount member and respectively provided between this mount member and the pair of friction pads (PTL 1).